The method of setting a travel locus based on geometric information of a road and performing travel control of a movable body traveling on the road is, for example, disclosed in Japanese patent document JP-A-H07-248819. The travel locus control method in the above document is about a steer angle of a steering wheel based on a geometrically set locus and a direction of a vehicle relative to the geometrically set locus.
However, when the travel locus of the vehicle that is driven by a driver is set based on the geometric information, the travel locus does not necessarily match a predicted travel locus that provides comfort for the driver of the vehicle. That is, in other words, the travel locus according to the road geometry may lead to a discomfort of the driver when he/she performs the travel control of the vehicle.
More practically, if the driver is driving a vehicle and steering by him/herself, the vehicle is steered to travel toward an “exit” of a curved road when traveling on the curved road. On the other hand, when the vehicle is traveling on a travel locus that is being set according to the geometric information of the road, the vehicle is not sufficiently steered toward the “exit” of the curved road, thereby giving the driver an impression that the vehicle is going to go off from the road; which leads to discomfort and/or unsafe feeling of the driver.